Telephone system for recording and reproducing transmissions



June 1, 1937. A. w. SCHILLER TELEPHONE SYSTEM FOR RECORDING ANDREPRODUCING TRANSMISSIONS 2 Sheets-Sheet 1 Filed Dec.

7 W: I I

J1me 1937- A. w. SCHILLER 2,082,303

TELEPHONE SYSTEM FOR RECORDING AND REPRODUCING TRANSMISSIONS Filed Dec.13, 1954 2 Sheets-Sheet 2 8 8 v 3% N: R

172567220]? QZJMAM W'yml 5 Patented June 1, 1937 uuirso STATES PATENTOFFICE Alfred Walter Schiller,

Zurich, Switzerland, as-

signor to Otto Jaeger, Zurich, Switzerland Application December 13,1934, Serial No. 757,415 In Switzerland September 29, 1934 6 Claims.

This invention relates to telephone systems and is more particularlyconcerned with subscribers station arrangements comprising soundrecording and reproducing means which arrangements in addition torecording the transmissions are also adapted to record suchtransmissions that are intended to be used as dictations, so that theserecorded transmissions can be reproduced any number of times later.

According to this invention, this result is accomplished by correlatingto the telephone apparatus of a subscribers station the normal receivingmeans and loud speaker means in selectively connectable manner as wellas sound recording and reproducing means constructed on the sameprinciple as the magnetic sound reproducing devices and combining thesaid means through the intermediary of a wiring system, in such manner,that telephonic communication is rendered possible either by aid of thereceiver means or the loud speaker means each separate, or bysimultaneously recording the transmissions and reproducing the samelater on, or else by directly recording a dictation independently of thetelephone apparatus, so that the dictation can be reproduced any numberof times later.

Owing to this arrangement all telephonic communications can be recorded,if desired, preferably so that the recorded transmission is amplifled.Furthermore, a device may be provided which is set for ready operationby the subscriber, so that this device automatically responds to a callwhile the subscriber is absent and transmits to the calling party theline number of the station with the aid of .a talking machine such as agramophone and then gives the signal for the communication to begin,whereupon the latter is automatically recorded,

advantageously, without being amplified, to the efiect that a sharplyaccentuated record devoid of distortion is obtained in which theconsonants can be distinguished sufficiently clearly to render thereproduction intelligible. On his return the subscriber is enabled toreproduce all communications having been received and recorded in thismanner in his absence as many times as he may choose.

Moreover, the magnetic sound reproducing device may be adapted for useas a dictating device independently of the telephone service.

In the accompanying drawings a jorm of the invention is illustrated byway of rample only in which (Cl. 17H) Fig. 1 is a schematic top planview of the telephone apparatus;

Fig. 2 schematically illustrates a sound recording and reproducingdevice;

Fig. 3 shows a larger scale elevation of the sound recording andreproducing means;

Fig. 4 shows a plan view of the sound recording and reproducing meanspartly in section;

Fig. 5 shows an elevation of the driving arrangement of the soundrecording means;

Figs. 6 and 7 show a vertical section and a plan view respectively ofthe sound translator head or sound head on a still larger scale;

Figs. 8a and 8b represent two portions of the wiring diagram inclusiveof a switching chart, and

Fig.- 9 is a sectional view of a detail.

The station arrangement according to this invention comprises as' mainparts the telephone apparatus '1' and a sound recording and reproducingdevice R.

The telephone apparatus T as such consists of a usual apparatus of thedial switching type comprising a loud speaker, the calls being effectedby means of an ordinary dial-switch I.

The incomingcommunications can be received by means of a normaltelephone receiver or by means of the loud speaker 2. Furthermore, twomicrophones 3 are combined with the apparatus. The switching means foreifecting the various connect ons during operating the arrangement arearranged upwardly on the apparatus, viz. a push button switch a forchecking (a record), two lever key multiple switches 5 and 6 on bothsides of thddial switch I, and a lever key switch I for returh motion(sound record carrier wire or -sound wire). A pair of signal lamps isalso arranged on the apparatus, the lamp 8 of the pair serving forindicating that the end of the sound wire has arrived at its limit stop,whereas the other lamp 9 indicates that the motor for moving the soundwire is operative.

Above the two signal lamps a scale It is situated which is provided withan index I2 which is displaceable along a guide rod ill the scalepermitting observing the unwinding of the sound wire, so that the indexindicates at all times during a conversation the position of theconversation on the sound wire. The index is actuated by means of aBowden drive 13 the pull wire of which is wound on a spring influenceddrum it. The telephone apparatus further comprises besides two amplifiertubes i5 and I? and the necessary groups of contact arrangementsassociated with the lever key switches 5 and 6 naturally also allconnecting wires leading out through a cable connection l1 (/0 beconnected by means of a cable i8 and another cable connection i1 withthe sound recording and reproducing device R to which the pull wire ofthe Bowden drive I3 is anchored at one end. This device accommodates theentirety of recording and reproducing means the essential parts of whichare schematically illustrated in Fig. 2. The device is connected to thealternating current network via a network transformer I9 feeding a lowtension rectifier 29 together with an associated filter and a hightension rectifier 2| also combined with a filter.

The winding and recording device for the sound wire F which device willbe hereinafter more explicitly described comprises as main parts twowinding spools 22, 23, to which magnetic couplings 24 and 25respectively are correlated,

a magnetic sound head 26, and a driving motor 21 for alternatelyactuating the two winding spools by means of a belt drive. Fordisconnecting the magnets of the couplings for rendering the latterinoperative at the end of the wire two limit switch levers 2812. and 29h(Fig. 3) are provided which are mechanically operated by the windingdevice for controlling the magnetizing circuit of the correlated magnetsof the couplings 24 and 25 via the contacts of these magnets, in orderto prevent the wire F from being torn when recording is effected up tothe end of the wire. In addition thereto, with each magnetic couplingauxiliary motor contact groups 18 and 19 are associated.

Furthermore, with the device R a response talking machine 32 having apick-up arm 33 is combined, this machine being automatically operatedthrough a call-relay 34 when the station is rung up, this relay servingat the same time for controlling a main relay 35. The latter has theoflice together with a ring-off relay 36 to automatically control therecording of telephone transmissions.

The shafts of the two winding spools 22 and 23 are mounted together withtheir driving means on the one hand in the face plate 40 of the device Rand on the other hand in a web plate 41 positioned behind said faceplate, the two winding spools being housed in a removable casing 42 onthe outside of the face plate.

As the mountings and the drives of the two winding spools are identical,these parts will be hereinafter described by taking reference to one ofthese spools only. From Figs. 3 to 5 it is evident that to the forwardlyprojecting end of a winding spool shaft 43, mounted in ball bearings 40and 4i, a disk 44 is fixed, for example by means of a key, the diskserving for the adjacent end of the winding spool to bear against andbeing provided with a number of perforations one of which is engaged bya driving stud 45. On the inner end of each winding spool in a recessthereof, a leaf spring 220. is secured to the outer end of which a stud22b .is fastened and which is held by the perforated plate 44 in aposition as shown in Fig. 9.

On retracting the casing 42, spring 22a is released so as to force thestud 22b into engagement with a hole 420, of a punched rim of thecasing, thus securing the winding spool against rotation. On thebackside of the web plate 4| a coupling magnet 25 is mounted thearmature 4B of which carries, by means of two bolts 41, a pressure disk48. On the shaft 43, in front of the pressure disk 48 a coupling disk 49is mounted so as to be longitudinally slidable but kept from rotation,this disk being spaced from a mating coupling disk 50 by an interveningcompression spring 5|, in such manner, that during the time ofinoperation the two disks are prevented from engaging. The coupling disk50, which is in the form of a belt pulley. is mounted in ball bearings.50 as to rotate around shaft 43 but kept from displacement along thesaid shaft. When the coil of the coupling magnet 25 is energized, itsattracted armature 46 forces, by means of the pressure disk 48, studs49a on the coupling disk 49 into engagement with complementary teeth onthe coupling disk 59, and, as the latter is rotated by the winding motor21 by means of a belt 52, the spool 23 is also turned to wind thereonthe sound wire F payed out by the spool 22,

As shown in Fig. 3 the sound wire unwinds from the upper side of thespool 22 and is wound onto the lower side of spool 23 adapting the motorto run at all times in the same direction of rotation irrespectivewhether the wire is wound on one or the other spool. For tensioning thebelt 52 a tensioning roller 53 is provided. The construction of thewinding means thus far described is identical for both winding spools.

The shaft 43 is further provided with a worm thread-43s which mesheswith a worm wheel 54 which is situated on the upper end of a shaft 55mounted in oblique disposition on the backside of the face plate 40 andprovided at its lower end with a worm thread 56 into which a worm wheel51 engages. This wheel is secured on a shaft 59 which ismountedtransversely between the face plate 40 and the web plate 4| and thefront end of which projects out of the face plate 40 and which carriesalso a cam 59. Above the shaft 58 an axle is longitudinally displaceablymounted in parallel relation with the same so as to project into thecasing 42 with its forward end.

To this axle a guide fork 6! is secured which embraces the cam 59 andengages into a guide groove of this cam by means of a pin, so thatduring the operation the axle 60 is continually pushed to and fro by acertain throw which corresponds to the length of the guide groove of tthe cam 59 and thus to the width of the spools 22 and 23.

On the forward end of the axle 69 the sound head 26 is secured whichshares in the reciprocating movement of this axle so as to ensure thatthe sound wire T after having passed the sound head is wound in uniformlayers onto the respective spool 22, 23. To the forward end of the shaft58 a bevel gear wheel 62 is fixed which is in mesh with a bevel gearwheel 63 which is secured on a screw spindle mounted in the casing 42parallel with the face plate 40. On this spindle a screw nut 65 ismounted for longitudinal displacement thereon and guided in alongitudinal slot of the casing so as to depend downwardly therefrom forreceiving the pull wire of the Bowden drive !3 in an easily detachablemanner.

The stop levers 28h and 29h of the limit switches 28 and 29 project intothe path of movement of the nut 65 at either end of its traverse. Theratio of gearing of the driving mechanism between the shaft 43 and thescrew spindle 64, i. e. the screw nut 65. is so chosen that during thecomplete winding or unwinding of the sound wire F the nut 65 travelsfrom one end of its traverse to the other to alternately actuate thestop levers 28h and 29h cooperating with the limit switches 28 and 29,so that the correlated coupling magnets 24 and respectively are operatedfor disconnecting the couplings 49, 50 of that spool which is thenwinding on and at the same time for stopping the driving motor 21 inorder to avoid breakage of the wire. The movement of the drivingmechanism is transmitted to the index l2 of the device T by means of theBowden drive thus permitting to read on the scale II the length forwhich the sound wire has been shifted in either direction. The casing 42is fastened to the device by means of two lateral spring-influencedlatches 66, so that the casing can be readily removed together with thetwo spools after the sound head 26 has been opened and the pull wire ofthe Bowden drive I3 is detached. It will be understood that a screwspindle 64 and a bevel gear wheel 63 are provided in each spool casing.While pushing the casings into position, the driving studs 65 of thespools are held in the perforations of the correlated disks 44, so thatthe bevel gear wheel 65 is caused to intermesh the bevel gear wheel 62automatically.

The sound head 26 (Fig. 6) is made in two parts and contains two pairsof magnets 10 and 1| the individual magnets of each pair being offsetrelatively to one another for about the width of a magnet core. The pairof magnets ll serves for pre-magnetizing and checking and the other pair10 for recording on the sound wire passing between the magnet coreswhile being talked. The pairs of magnets 10 and H are embedded in thetwo halves of a body .member; 26t, each of these halves being providedon the inner side with a glass plate 26a. The respective ends of themagnet cores are flush with the exterior sides of the glass plates andare joined therewith by means of putty. Owing to this construction theportion of the sound wire F passing between the glass plates thoughcontacting with the magnet cores is prevented from causing wear thereon.At each end of the upper half of the body member 26t two guide plates26b for guiding the sound wire laterally are arranged, each pair ofthese plates being separated by an intervening spacing plate 260.

In consequence of the magnet cores being offset relatively to oneanother a thorough magnetic saturation of the wire practically devoid ofdispersion is obtained, so that notwithstanding the very low speeds ofthe wire down to 0.5, meter per second a clear reproduction devoid ofdistortion ensues, the wire being pre-magnetized before every recordingoperation. The device is provided laterally beneath the cable connectionI! with terminal studs 31 (Fig. 3) for connecting it with thealternating current network, whereas further terminal studs 38 serve forconnection with the telephone wires a and b.

The wiring diagram for the entire station arrangement is illustrated inthe Figs. 8a and 8b inclusive of a switching chart for the differentpositions of the lever key switches 5 and 6. Concerning the variousapparatuses as far as these have not already been more particularlydescribed above, the following explanations are given:

The network transformer is serves for connecting the station arrangementwith an alter-. hating current network of 100-250 volts tension and -60kh. and is provided to this end with tap points for certain intermediaryvoltages. The alternating current energy is on the one hand directlysupplied to the driving motor 21 for actuating the drive of the windingspools and on the other to the driving motor for the response talkingmachine 32, 33. Both motors are of the normal monophase induction typehaving a short circuited rotor. The record of the talking'machine can betalked in the following manner.

Here No. Frederic Brown, please speak slowly and clearly, yourcommunication will be recorded. The talking current impulses that aretransmitted during the then following communication are led directly tothe modulating magnets 10 of the sound head 26, so that the recording'on the sound wire is effected without amplification. The low tensionrectifier 20 and the high tension rectifier 2! are of thedry plate typewhich renders the device fit for ready operation at all times withoutthe necessity of waiting for tubes to heat up.

The main relay 35 consists of a direct current relay, the call-relay 34and the ring-off or final relay 36 are high ohmic alternating currentrelays. Furthermore, for the recording of dictations, the reproductionand for the loud speaker telephone transmission a two-tube low frequencyamplifier 12 is provided.

The telephone apparatus T is provided with a call-alarm buzzer 73 forthe ordinary telephone traific and a selector switch 14 and as callingand dial switching is efiected as usual further describing andillustrating the respective devices can be dispensed with. 15 refers toa microphone inseparably connected to the telephone apparatus, the loudspeaker 2 may alternatively be replaced by a normal telephone receiver.By 16 a return motionswitch for reversing the movement of the sound wireF is designated and by 1! a switch for checking the recording operation.The lighting of the signal lamp 9 indicatesthat the winding motor 21 isoperative, whereas the lighting of the signal lamp 8 indicates that thesound Wire F is completely wound ofi, from one or the other spool. Withthe coupling magnets 24 and 25 of the couplings of the winding spoolsthe necessary' motor control contact keys 18 and auxiliary contact keys19 are correlated.

The two lever key switches 5 and 6 serve for controlling the individualoperations in their different positions of setting, that is, the middleor normal position m and their ofi-positions l and r to the left andright respectively. The lever key switch 5 controls the groups ofcontact springs or keys 8l1-v and 831 iv and the lever key switch 6, thegroups of contact keys 84r-1v and 851411. In all the contactarrangements of these groups as well as all the others the individualcontact springs or keys of each pair are designated by a and brespectively. The brief chart at the top of the wiring diagram indicatesthe difierent setting of the two lever key switches for the variousswitching combinations, wherein the character T stands for normaltelephone: trafiic, T and Re telephone traffic combined with recording,D recording of dictation, Rp reproduction of dictation, and ARgautomatic recording of telephone transmissions.

The operation of the station arrangement described will be hereinafterexplained by taking reference to the wiring diagram, while it is assumedthat the following connections are permanent, that is, permanently putin.

The positive pole of the anode potential, 1. e. the conductor Hllextending between the rectiher and the amplifier, the negative biasedvoltage conductors I02 and I03 01 the grid, the middlepoint of theheating conductor 105 which point is connected to earth at E and to thezero point of the source of anode potential, and the negative pole ofthe source of heating current I04 for the tubes of the amplifier 12. Inthe normal position m of the lever key switches 5. and 6 the rectifieris permanently connected to the network 31A and 313, the amplifier I2 isunder tension but without being heated, as the connection between thetube heater arrangement and the source of heating current llli isinterrupted by the contact keys 85v: and 8311 of the lever key switches5 and 6 being connected in parallel. The telephone line 38a}: is closedvia the selector switch contact 1411, condenser 69, call-alarm device13, contact keys 841i and "V of the lever key switch 6 and contact keys8211 of the lever key switch 5.

When the station is called up, the call-alarm buzzer operates. Thecalled party thus being advised of a call changes the lever key switch 5over to position r, whereas the lever key switch 6 remains in position111.. Thereby the call-alarm clock circuit 38b, Mn, 69, 13, 8411, 8211,3811 is interrupted at contact keys 8211. Howeven'bef ore contact keys82m open, contact keys 82111 are already closed, so that the telephoneline conductor 38a, is not interrupted but connected to point a ofinduction coil 88 the other end of which is permanently connected toconductor 38b via selector switch M11. The amplifier heater arrangementcircuit is closed at contact keys 82v, the amplifier thus being preparedfor operation.

The microphone 15 is connected to point a or b respectively of theprimary side of the induction coil 86 via the contact keys 85118,) or mmof the lever'key switch 6 which is in condition of rest. Point d on thesecondary side of the induction coil is directlyconnected to the inputterminal 93 of the amplifier I2 via the contact keys 82m then closed ofthe lever key switch 5, whereas point e of the induction coil 88 isconnected to the second amplifier input terminal 92 via a damper-windingresistance 81 and the contact keys 821 then also closed of the lever keyswitch .5. The talking current impulses amplified in the amplifier l2flow from the amplifier output terminal 94 via contact keys 841 which isclosed in the normal condition of the lever key switch 6, via thecompensating resistance 88 to the terminal 2?) of the loud speaker, i.e. from the amplifier output terminal 95 via the contact keys 85mm ofthe lever key switch 6 which contact keys are also closed in theposition of rest of this switch, to the other terminal 2a of the loudspeaker, the loud speaker thus reproducing the incoming telephonetransmission. The damper winding resistance 81 is so adjusted that anacoustic back coupling eifect between the loud speaker 2 and themicrophone 15 is avoided.

If instead 01 the station being called up from outside calling from thestation is desired, at first the lever key switch 5 is movedintoposition 1-, while the lever key switch 5 remains in position'ofrest, as before, in which way all the switching connections describedimmediately above are completed. As soon as the signal line free" isheard from the loud speaker, the desired line member is selected bymeans 0! the dial switch, so that, in a known manner, the contact keysI411 interrupt the line circuit, while at the same time at contact keys141 the induction coil is short-circuited. On the termination of theselecting operation contact 141 of the dial switch is opened to removethe short-circuit from around the induction coil, whereupon theapparatus is in condition for conversing.

When it is desired to record the conversation, the lever key switch 6which up to this time had remained in position of rest, is set toposition r, while the lever key switch 5 further remains set toposition 1. In this manner the contact 25a of the coupling magnet 25 foradvance motion, the contact 25!) of which is permanently connected tothe positive pole llll of the anode potential via. the limit switch keys29118 is connected to the negative pole 96 of the anode potential viathe already previously closed contact keys 82 IV,a,b of the lever keyswitch 5 and the but then closed contact keys 84mm; of the lever keyswitch 6. In comequence thereof, the coupling magnet 25 attracts itsarmature and connects the dog clutch for advance movement of the soundwire. At the same time this magnet actuates the contact keys 19mmthereby closing a circuit from the alternating current network via thepermanent connection 99, 211) main motor, 21a 1911, 98, so that the mainmotor starts to run. In addition, the coupling magnet 25 also closes thecontact keys 191,8 thereby closing a circuit from the branch conductor9| of the low tension alternating current winding via the permanentconnection 9|, 8b, the signal lamp of the motor, 8a, 191,8 and back tothe branch connection 90, so that the signal lamp I of the motor is lit,thus indicating that the motor runs. The sound wire F is thus set inmotion and prepared for receiving a record. When the switch 6 was settoposition r the following iurther circuits have been established:

The circuit of the premagnetizing coils II is closed via the positivepole ill! of the source of potential of the anode, the permanentconnection NH, 95, the contact keys 8411mm then closed of the lever keyswitch 6 and terminal Ha. oi the pre-magnetizing coil 'Il, through thelatter and from the terminal 'llb via the permanently connectedresistance 61v and the permanent connection 61, I03 to the negative poleof the source of anode potential. Pre-magnetizing current now flowsthrough the coils H for pre-magnetizing the wire F and at the same timeremoving all modulations that may be present on this wire. Contact keys841mm open, which is, however, of no effect at this time, as the contactkeys 821m of the lever key switch 5 which are connected with the formerkeys have previously opened. Contact keys N1, of the lever key switch 6are thus opened to close contact keys 84I,a,b, so that the followingcircuit is established:

The output energy of the amplifier no longer passing from terminal 94via the contact keys m as before to the compensating resistance 88 andfrom there directly to the loud speaker 2, flows via contact keys 84mmto point 61111 of the potentiometer Bi! and from there in certainproportions partly through the section 61m, 61a of the potentiometer andpartly through the section 61m, 61c then of decisive importance of thepotentiometer, through the condenser 68 and modulating coils 10 to point111 of potentiometer 61 and from there via the return motion trippingcontact keys 181x, 0!

-' tential 96.

the coupling magnet 24 for return motion which keys are closed duringthe advance motion, and then through the closed contact keys 831m, ofthe lever key switch directly to the loud speaker terminal 2b. Thepotentiometer 6'! for controlling the degree of modulation of the wire Fand the resistance 88 are so balanced relatively to one another that theexterior resistance of the amplifier 12 remains constant so that,provided that otherwise the existing conditions remain unchanged, thestrength of sound in the loud speaker with the reproduction means put inor out remains constant.

By effect of the portion of the amplified alternating talking currentflowing through the modulating coils the wire F is, in a known manner,magnetized to variable saturation in conformity. with the frequency ofthe talking current impulses and proportionally to the amplitudesthereof. If during the recording the wire F is completely wound off, theapparatus 43 to 65 for counting the number of meters of wire payed out,the speed of which is highly accelerated, actuates at first the switchkeys 291' of the limit annunciator signal lamp so that this lamp 9, theterminal 9b of which is permanently connected to the branch conductor SIof the low tension alternating current winding of the main feedtransformer I9 is supplied with current via the terminal 90 of the lowtension winding, the terminal l9a, the then closed contact keys 291,54;and a permanent connection, and is thus lit.

The lighting of this lamp indicates that only a short length of wire isstill available for the recording operation. If this operation isnevertheless continued, a short time later the key contacts 2911,53 areopened by action of the apparatus for coupling the number of meters ofwire payed out referred to immediately above. In this way the circuit96, 84mm, 82mm, 25a,b, 2911,, H of the coupling magnetizing current isbroken and thus the coupling magnet 25 released, whereby the drivingarrangement of the wire winding device is set at standstill bymechanical means. Incidental to the coupling magnet releasing, thecontact keys 1911, and 191, operated by this magnet are opened inconsequence of which on the one hand the motor circuit 99, 21b, 21a,1911,11, 191m, 98 is interrupted and therefore, the main motor 21 isstopped, and on the other hand the circuit 9i, 8b, 8a, 191, 90 isinterrupted, so that the mo tor signal lamp 8 is extinguished, thusindicating that the motor is at standstill. Due to the limit contactskeys 8911 for advance motion having been opened, it is thus impossibleto operate the coupling magnet 25 for advance motion in any positions ofany lever key switch with a view to starting the motor, which wouldresult in breakage of the wire.

As obviously the-necessity exists to wind the wire back after it iscompletely unwound and at this time the respective switching operationis the only one that can be carried out in regard to the movement of thewire, the switch 15 for effecting the return motion is operated afterthe lever key switch 6 has been set to normal position m. Inconsecfuence thereof the following circuit is established:

From the negative pole of the source of anode potential 96, via returnmotion switch contact keys 16a, 1), return motion coupling magnet 24b,24a, return motion limit contact keys 281,8,b to the positive pole "H ofthe source of anode po- Consequently the return motion coupling magnet24 energizes to connect the coupling for effecting the return motion ofthe sound wire. At the same time the return motion coupling actuatesduring its shifting movement the following contact arrangements: contactkeys 18III,a,b which are in parallel with the two contact keys 1911, thelatter being, however, open at this time. Thus a circuit is establishedfrom the alternating current branch conductor 99 through the drivingmotor from 21a to terminal 21b thereof, through contact keys 18111, andfrom there back to the alternating current network through branchconductor 98, so that the driving motor 21 starts to move again.

The direction of winding of the sound wire is, however, now reversed, bythe return motion coupling 24 being connected. The motor signal lampcircuit is closed at the contact keys I81, so that the connection fromthe low tension winding through branch conductor 9|, signal lampterminals 8b, 8a, coupling magnet contact keys 18m, 181,1, branchconductor 90 and back to the low tension winding is established, so thatthe signal lamp 8 is lit thereby indicating that the motor 21 isoperative.

During the end of the return motion the counting apparatus for thenumber of meters of wire payed out actuates similar contact arrangementsas during the advance movement beginning with closing a contactarrangement 281i of a return motion limit annunciator signal lamp. Inthis manner, the end signal lamp 9 is supplied with current through acircuit which continues from conductor 9| via 9a, 8b limit contactarrangement 281mm, back to conductor 90, thus indicating that the end ofthe wire approaches. If the return motion is nevertheless furthercontinued, the limit contact arrangement 281,34, of the respectivecoupling magnet is opened to interrupt the coupling magnet circuit 96,16a, 16b, 24b, 24a, 2819., 281b, IIH so that the coupling magnetreleases. Consequently the motor circuit 99, 21b, 21a, 18III,b,a, 98 isbroken, the motor 21 thus being set at rest. Therefore, further returnmotion of the sound wire F is prevented, the only possible way of movingthe sound wire being forwards by operating the respective lever keyswitch.

Duringthe return motion the return motion coupling magnet 24 effectsalso the opening of the contact keys 1811,, thus ensuring that themodulating coils 10 are disconnected in any circumstances, in order toprevent current from flowing through the modulating coils I0 and thuscausing undesirable modulating effects by any erroneous switchingoperations or leakage Automatic recording of telephone transmissionsWhen a telephone call is received from the line in the absence of thecalled party, the latter is adapted to prepare for the stationarrangement operating automatically to answer the call and record theincoming communication by setting the lever key switch 5 to normalposition and setting the lever of the switch 6 to position 1. Thissetting of the lever key switches can be effected in advance as nocircuits are closed in. this manner to the effect that electric energyis consumed; By these preparatory switching operations the followingconnections are ef- .fected.

The call current impulses (alternating current of about 30 Hertz) flowvia terminal 38b of the telephone service connection via the selectorswitch 1411, condenser 69 to the alternating current relay 34 and fromthere via the closed contact keys 35m of the direct current relay 35 tothe then closed contact keys 8411a,]: of the lever key switch 6, throughthe also closed contact keys 821mm of the lever key switch and backagain to the terminal 38a of the telephone service connection.Consequently the relay 34 energizes thereby closing the contact keys 34xand 3411. Direct current then flows from the positive pole llli of thesource of anode potential via the direct cur'rent relay 3521,19 andcontact keys 341,84 to the negative pole of the source of anodepotential 96, thus causing this relay to energize. At the same timecurrent is fed to the motor of the gramophone 32 through a circuittraced from conductor 98, through the contact keys 34 m having justclosed of the alternating current relay 34 back to conductor 99 via32b,a, this motor thus starting to run. Due to the direct current relay35 having been energized holding contact keys 351w, are closed, so thatcurrent can flow through relay 35 independently of the contacts of relay34 from conductor lcl through the .closed contact keys 361, of the finalrelay 36 and the holding contact keys 351mm) to 96, thus maintainingrelay 35 in energized condition.

Due to relay 35 having energized the commutation contact 3511 is changedover from position 35m to position 35mm. In this way the callrelay isde-energizedso' as to release, as the circuit 381), 1411, 69, 34awinding of relay 34 and its contact 3417, 3511c, 35m, 84m, 8411b, 821m321m, 38a is interrupted at contact keys 351mm. The relay however,remains still energized by efl'ect of the above-mentioned holdingcontact keys being closed. But, upon energization the relay 35 effectsin conjunction with contact keys 3511 the changing-over operation whichotherwise is effected by lever key switch 5 at contact keys 8211,5 Thisis due to the fact that at this time a circuit is closed, from thetelephone service connection 33a, via 82m 84mm, 35mm, 311mb, 1811! Ha,100,1), 35mm, lflflm to 3817. In this condition of the stationarrangement the sound wire F is directly talked by the communicatingparty, thus without amplification, which method results in a very goodreproduction devoid of distortion. Furthermore, in this peculiarcondition of the system listening to the telephone transmissions bythird parties is entirely obviated, as the loud speaker as well as themicrophone are put out, perfect discretion thus being provided for theconversation transmitted through the apparatus by the communicator. TheDre-magnetizing cooperation is effected through a circuit from 95(ifll), contact keys 841m pre-magnetizing coil 1 I a,b and resistance61v back to I03. By energization of the main relay- 35 the couplingmagnet 25 for advance motion is supplied with current through thecircuit 95, alrvma, 35mm, 25a,b, 29m and HH, and at the same time themain motor 21 is started in the manner previously described. Moreover,the wire feed is stopped upon release of the relay at the end of theconversation, due to the contact .keys 35I,a,b openin When thecall-relay 34 attracts its armature by means of alternating call-currentimpulses, the talking machine starts to run as aboveexplained, but wouldbe stopped again incidental to the call-relay releasing. However, atthis moment a cam disk 321i driven by the motor has moved through anangular displacement of such an extent that two contact arrangementsI001 and H1011 are then closed one of which closing that circuit throughthe motor in parallel with the corresponding contact arrangement of thecall relay which thus upon release of the call-relay continues from 99through the motor 32, cam contact arrangement 100mm to 93, so that themotor is maintained running. At the same time the pick-up arm 33, oneterminal 33:: of which is permanently connected to the serviceconnection 38a, is put with its other terminal on the terminal 382) ofthe service connection through the contact arrangement |oI,a,b thetalking current frequency thus passing out from the pick-up arm into theline only without being unnecessarily recorded. In the meantime thesound wire is idly kept in motion, so that desirable intermissions areobtained between the various recorded conversations.

While the automatic telephone response means have transmitted the numberand name and so forth of the subscriber and have given the signal forthe conversation to begin the cam disk 3211 has completed onerevolution, whereupon the motor contact arrangement llliin opens again,thus stopping the motor, as the circuit 98, 32a,b, 1001M, 99 is nowinterrupted. At the same time the line conductor 33b is disconnectedfrom the pick-up arm and connected to the main relay 35 again by meansof changeover switching, so that the initial circuit for recording isre-established. The calling party may now speak while the conversationis recorded.

When the calling party has finished talking and replaced the receiver,the thus arising abrupt current impulse causes the extremely sensitivehigh-ohmic relay 36, which during the talking connection was connectedacross the telephone line 38 in parallel with the talking circuit from38b through the condenser 33, 36a,b, 34mm, 821mb to 38a, to suddenlyenergize to open the contact keys 361, whereby, however, the holdingcircuit lOI, 35:11), 361-, 3612;, 351v, 96 is broken and the main relay35 is released, so that the coupling magnet 24 is devoid of current andthus the main motor 21 is stopped, the station arrangement being thusrestored to original condition ready for receiving a call.

Applicability for dictation When it is desired to use the arrangement asan ordinary dictation apparatus, the lever key switch 5 is set to normalposition and the switch 8 to position I. In this way the coupling magnet25 is energized via the circuit 98, 85mm, 35. 29m lOi and the couplingfor advance motion is connected and the main motor 21 is operated in thehereinbefore repeatedly explained manner. At the same time the amplifierI2 is prepared for operation by connecting the heater arrangementthereof via the circuit I04, contact keys 85vn,b. amplifier I2. Themicrophone I5 is connected to the input terminals of the amplifierthrough the direct current low tension circuit I04, contact keys 85n,b,amplifier input terminals 92,

93, contact keys 85mm. microphone 151 contact The output side of theamacsasoc condenser 68, potentiometer tic; E'im and back through theresistance as and the contact keys 851ve,c,- to the output terminal 95of the amplifier, so that the wire F can now be talked by means of themicrophone and thus the arrangement can he used as a dictationapparatus. Furthermore, in this condition of the arrangement provisionis made that the loud speaker is prevented from operating during thedictation, so as to ensure that the transmission which otherwise may bedisturbed is plainly intelligible, by disconnecting the terminal 2a ofthe loud speaker from the output terminal 95 of the amplifier at thecontact keys 851Va,b.

The pre-magnetizing operator is connected via the circuit 95 (NH),contact keys a5IV,n,c, premagnetiaing coil Ha, 'llb, resistance 611:,I03.

Reproduction of recorded communications or dictations coupling 25 foradvance motion is put in through a circuit from 96 through contact keys.31vn,b, 25a, No, limit stop contact arrangement 29mm to ill! and thedriving motor 21 is rendered operative in the manner previouslydescribed. The alternating electromotive force induced in the modulatingcoils by the magnetic modulation in consequence of the moving wirecirculate through the circuit Illa, 61a, return motion limit contactarrangement 781mm, contact keys 83mm.- to the input terminals 92, 93 ofthe amplifier and from there again back via contact keys 83m to themodulating coil 10b. The output of the amplifier circulates from theoutput terminal 94 via the contact keys 84m of the lever key switch 6 tothe compensating resistance 88 and from there to the loud speaker 2b, 2aand back via the contact keys 85mm; of the lever key switch 6 to theoutput terminal limit annunciator signal lamp 95 of the amplifier. Thetalking current frequency arriving from the modulating coils is thenaudible in the loud speaker.

In order to permit of checking the conversations entirely or partly,provided that they have not already been checked every time a freshrecord'was made, a check push button switch 11 is provided whichsupplies the pro-magnetizing coils 1| with direct current through acircuit from the negative pole 903 of the source of anode potentialthrough the resistance 61o ore-magnetizing coils from 'llb to Ha, topush button switch i1 and to the positive pole lfll, thus vided for eachwinding spool so as to be adapted to actuate the driving shaft of therespective spool through the medium of a unidirectional clutch in suchmanner that during winding the sound wire on one of the spools the motorof the other spool is at standstill and thus no resistance is opposedtothe starting movement by inertia of ineffectively moving masses.

Alternatively, the sound head may be constructed in such manner that thecores of the magnets are longitudinally displaceably mounted and urgedon the sound wire by spring action.

I do not limit myself to the particular size, shape, number orarrangement of parts as shown and described, all of which may be variedwithout going beyond the scope of my invention as shown, described andclaimed.

What I claim is:

l. Sound recording and reproducing means, including a magnetic soundtranslator, a driving motor combined with said sound translator,actuating means coupled to said motor, a sound record carrier wireadvanced and returned through said sound translator by said motor by aidof said actuating means; means including a first "signal lamp adaptedfor indicating the operated condition of said driving motor and meansincluding a second signal lamp for indicating: that said sound recordcarrier wire has completed a passage through said sound transator.

2. In an arrangement of a telephone subscriber's station adapted forrecording and reproducing the transmissions, in combination, a telephoneapparatus including a microphone, normal receiving means, loud speakermeans and sound recording and reproducing means associated with saidtelephone apparatus by a wiring system including control means inselectively connectible manner, a rectifier and amplifier aggregateincluded in said recording means for operating said loud speaker means,a magnetic sound translator included in said sound recording andreproducing means, and an adjustable damper winding resistance comprisedby said wiring system located in the circuit of said loud speakerwhereby to avoid acoustic back coupling between said loud speaker meansand said microphone.

3. Sound recording and reproducing means, including a magnetic soundtranslator, a normally stationary driving motor combined with said soundtranslator, a sound record carrier wire, two winding spools, adisconnectible electro-magnetlc coupling intercalated between said motorand each of said winding spools, energizing coils for saidelectro-magnetic couplings,

switching means included in the circuit of said electro-magneticcouplings for alternately connecting or disconnecting said couplings forwinding said wire on the driven spool by action of said motor, while theother spool is released for unwinding said wire, for advancing orreturning said wire through said sound translator respectively, limitswitch arrangements for said disconnectible electro-magnetic couplings,a stop means cooperating with each of said limit switch arrangements, a.screw nut cooperating with either of said stop means, a driving memberreadily removably connected to said screw nut, a screw spindlethreadedly engaging said screw nut, a speed reduction gear operativelyconnecting said screw spindle with one of said winding spools fortransmitting the rotational movements of the respective spool to saidspindle for stopping said sound record carrier wire by said screw nuttravelling longitudinally thereon at the end of the respective passageof said wire through said sound translator, and a scale cooperating withan index, said index being operatively connected with said drivingmember for indicating on said scale the length of said wire passedthrough said sound translator.

4. Sound recording and reproducing means, including a magnetic soundtranslator, a driving motor combined withsaid sound translator, a soundrecord carrier wire, two winding spools adapted to be alternately drivenby said motor to wind said wire on the driven spool while the otherspool is unwinding said wire, for advancing or returning said wirethrough said sound translator respectively, a coupling member providedon each of said winding spools, a driving shaft for each of saidwindings spools, a complementary member to said coupling member providedon each of said driving shafts and adapted to engage with the correlatedcoupling member in different angular positions of the respective drivingshaft, a casing surrounding said winding spools and adapted to beremovably pushed into position of use to provide engagement between saidcoupling members and said complementary members, a spring catchintercalated between each of said winding spools and said casing, saidspring catches releasing when said casing is pushed into position of useand locking said winding spools to said casing when the latter isremoved to prevent distortion of said winding spools in said casing andto provide immediate operative engagement between said driving membersand said complementary members, when said casing is pushed into positionof use again.

cation system, a telephone subscriber's station comprising a telephoneline, receiving means and speech transmission means adapted forconnection to said line, a telephone answering and message recordingdevice comprising a phonographic apparatus including a record having theoutgoing message recorded thereon, and a pick up device to cooperatewith said record, sound recording and reproducing means associated withsaid telephone subscriber's station including a magnetic soundtranslator, circuits operatively interconnecting said telephonesubscribers station and said answering and message recording device, andswitching means comprising a pair of key controlled multiple circuitswitches for selectively controlling the interconnection of saidsubscriber's station and said recording and reproducing device wherebyto provide individual and combined operation thereof.

6. The combination of claim 5, wherein one of said pairs of keycontrolled switches is adapted to condition said circuits to cause saidphonographic apparatus to repeat the message on the record thereof tosaid line, and to cause said answering and message recording device torecord speech currents transmitted over said line, and a relay operatedby ringing currents received over said line to initiate operation ofsaid phonographic apparatus and said answering and message recordingdevice, automatic means to terminate operation of said phonographicapparatus after transmission of the recorded message, and a second relayoperated over said line to terminate operation of said answering andmessage recording device.

ALFRED WALTER SCHILLER.

